It’s a universal benefit awarded to people with children, no matter what the parents’ circumstances, whether poverty-stricken or super-rich.

The intention is that it’s spent on the children – not cigarettes, alcohol or handbags.

The five Labour leadership candidates have all pledged to keep this universal benefit.

The Tories, meanwhile, have asked the renegade former Labour minister Frank Field, who was once told to “think the unthinkable” by Tony Blair, to do the same again.

He’s had a go but what he’s thought is not unthinkable, it’s unworkable.

Mr Field suggests halting benefits when your child turns 13.

That’s when mums who’ve taken time off for childcare are expected to be back in the workplace.

It’s also a time when a child needs parental support more than ever.

Mr Field says that “if you have a crisis at work and can’t be home, it’s not such a disaster as when you have a seven-year-old coming home from school”. Er, it is if you’ve got an isolated 13-year-old pursued home from school by bullies or consumed by peer pressure, alcohol, drugs and goodness knows what else.

A tax on Child Benefit for higher earners is another suggestion.

Is the tax office equipped to do that? I doubt it. And how much would it cost to run?

You may as well means-test in the first place and save the bother.

What’s needed is to think the really unthinkable.

It’s what increasingly disaffected childless couples and singles have been thinking for a long time.

Why should they fork out for other people to have children (or a cigarette or shopping habit)?

Why should they pay for the 43% of Child Benefit which goes to those on above-average incomes?

Maybe it’s time to dump Child Benefit altogether and work on a fairer integrated tax and benefits system instead.